Method of producing coated material



Au .23,193s. R BREA E 2,128,214

METHOD OF PRODUCING COATED MATERIAL Original Filed Nov. 28, 1954 2 Sheets-Sheet l 1938- R. w. B. READE 2,128,214

METHOD OF PRODUCING COATED MATERIAL Original Filed Nov. 28, 1954 2 Sheets-Sheet 2 METHOD @F IPRODFUG CGATED MATERHAH.

Ralph W. B. Reade, Port Wangton, N. Y... aa-

signor to United States (tyr I. Company, Chicase, 111., a corporation of 122.1.

Original application Novemr 23, 1934, serial No. 755,118. Divided and t application September 27, 1937, Serial No. 165,823

5 Ciai.

This application is a division of my prior application Serial No. 755,118, filed November 28, 193%.

The invention relates to a method of producing coated material and has particular relation to the manufacture of roofing material coated with a substance having a desired surface or texture generally known intheart as a corrugated surface.

Prepared roofing materials are ordinarily produced by a continuous process whereby a web or foundation sheet' of felt or other material is saturated or impregnated with an asphalt or other substance having a relatively low melting point and thereafter coated on one or both faces with an asphalt or other substance having a relatively high melting point in order to withstand the heat of the sun and the action of other elements. In this coating process, coating rolls are ordinarily employed to apply the coating sub-.

stance in the desired manner after the web or foundation sheet has been immersed therein, and it has heretofore been the practice to have these coating rolls either driven at a peripheral speed corresponding to the lineal speed of the sheet or to have them driven at a much lower speed or maintained stationary. b

The stationary roll arrangement has been used extensively in the manufacture of smooth surfaced roofing material, and in this manner the amount of coating on the sheets is calipered to the desired thickness.

This arrangement is subject to the disadvantage, however, that small particles of foreign material sometimes accumulate into lumps and wedge themselves between the coating rolls where the sheet enters and thereby cause streaks in the roofing. In order to avoid this, it has been customary in some instances to turn these rolls very slowly, for example, at two or three revolutions per minute, which may give a peripheral speed corresponding to not more than 5% of the lineal speed of the sheet passing through the rolls. In this way any foreign material is carried along between the rolls and the streaks in the sheets are thus prevented and wastage of material is thereby avoided.

In the manufacture of the so-called corrugated surface roofing material having a leatherlike grain or so-called grapevine finish, it is customary to turn the coating rolls at a peripheral speed corresponding to the lineal speed of the sheet passing between the rolls. While this arrangement may give satisfactory results under some conditions, difficulty has been encountered in many cases in that the grain or texture of the surfaces of the finished sheet is long and coarse and of. unattractive appearance.

This is partlcularly true where the coating material that is being used is quite thick or where the rolls are rolls at a peripheral speed greater than the lineal speed of the sheet, and, further, that the grain or surface effect may be varied within desired limits by varying the amount of excess speed of the rolls. It is an object of this invention, therefore, to provide a method for producing roofing material of the desired grain or surface effect by contacting the sheet with a surface moving in the same direction as the sheet, but at a speed greater than the lineal speed of the sheet.

The invention will be more fully understood and other objects and advantages thereof will become apparent from the following detailed description of a preferred embodiment of the invention, considered in conjunction with the accompanying drawings forming a part hereof, in which:

Figure 1 is a diagrammatic plan view of a portion of a roofing machine embodying the mechanical features of the invention in a preferred form thereof;

Fig. 2 is a diagrammatic. side elevational view of the machine, showing the path of movement of a continuous web of material therethrough:

Fig. 3 is a fragmentary detail plan view showing the essential features of a speed change mechanism embodied in the machine;

Fig.4 is a fragmentary view, partly in section and partly in elevation, taken on the line 4-4 of Fig. 3, showing the arrangement and mode of operation of the coating rolls; and

Figs. 5 and 6 are views showing the surface appearance of sheets of. material coated in accordance with the invention but under different conditions, whereby different surface eflects are obtained.

Referring first to Figs. 1 and 2 of the drawings, the machine there illustrated for carrying out the improved method comprises a suitable support II for a roll I! of the sheet material to be coated. This material isfirst passed through a device i3 known as a "looper", wherein any desired preliminary treatment may be applied to the sheet. This type of device is well known in the art and requires no detailed description herein because it does not constitute a part of the invention, being illustrated merely to assist in showing the relationship of the invention to the machine as a whole.

From the looper l3 the web of material I 2a passes through a vat l4 in a number of loops to be impregnated with a suitable saturant contained in the vat. The web emerging from the saturator, as shown at l2b, is passed through another looper l5 wherein any desired further treatment may be carried out to prepare the saturated web for the application of the coating material thereto.

The web passes from the looper l5, as indicated at i2c, to a coating tank I6 wherein the desired coating material is applied thereto. This material, ordinarily consisting of a form of, asphalt, is relatively thick and viscid and the application thereof to the web is governed by upper and lower coating rolls l1 and I8, between which the webis drawn. The web leaving the coating rolls, as shown at i2d, passes through the remaining portions of the machine, designated generally by the reference character I9, and any desired subsequent treatment may be thus given to the coated material thereby. Inasmuch as the present invention has to do with the coating process and apparatus, however, it is not deemed necessary to illustrate or describe any further details of the machine, which may be of any desired and well-known type, except .to say that the coated sheet is drawn through the entire machine independently of any movement of the coating rolls.

The machine may be driven by an electric motor 20 connected through suitable transmission means 2i to a main line shaft 22 from which the various parts of the machine, including the loopers l3 and I 5 and the saturator H, are individually driven, The shaft 22 extends through a speed change mechanism designated generally by the reference character 23 and the coating rolls l1 and I8 are driven from the shaft 22 through this mechanism, as illustrated in detail in Figs. 3 and 4. Refen'ing to these figures, it will be seen that the shaft 22 carries a bevel gear 24 which intermeshes with a bevel gear 25 secured to a shaft 26, to the opposite end of which is secured the driving element of a clutch 21. The driven element of this clutch is secured to a shaft 28 which drives the coating rolls l1 and it through suitable gearing, including a driving gear 29 secured to the shaft 23 and intermeshing with a gear 30 secured to'the shaft of the roll IS. The gear 30, in turn, intermeshes with a similar gear 30a secured to the shaft of the roll l1, and the direction of drive is such that the two rolls are driven in the respective directions indicated by the arrows in Fig. 4. Thus the opposed faces of the rolls, contacting with the op-' elements of clutches 34, 35, and 36. The driven elements of these clutches respectively carry sprocket wheels 31, 33 and 39, which drive sprocket wheels 40, 4| and 42 by means of sprocket chains 43, 44, and 45. is secured to a countershaft 46, which also carries a sprocket wheel 41, driving a sprocket wheel 48 by means of a connecting sprocket chain 49. The sprocket wheels 4|, 42, and 43 are all secured to the roll driving shaft 28 which is adapted to be selectively driven through the three sprocket wheel and chain connections described, as well as to be directly driven through the clutch 21.

The clutches 21, 34, 35, and 36 are controlled by handles 50, 5|, 52, and 53, respectively, and

The sprocket wheel 43 are interlocked by means of any suitable wellknown mechanism indicated schematically by the dot and dash connecting lines 54a, so that not more than one of the four clutches can be engaged at any one time.

When all four of the clutches 21, 34, 35, and 36 are disengaged, the coating rolls i1 and I8 will be maintained stationary, for which purpose a brake (not shown) may be provided if desired. When the machine is operated with the rolls stationary, said rolls will serve merely as calipering means to regulate the thickness of the coated sheet as desired. In order to avoid the hereinbefore-mentioned disadvantages of using entirely stationary rolls, however, the clutch 34 may be engaged to drive the rolls at a very slow rate of speed, which is obtained by reason of the double reduction through the sprocket wheels 31 and 40 and the sprocket wheels 41 and 48.

For the type of operation in which it is desired to operate the rolls l1 and ill at a peripheral speed corresponding to the lineal speed of the sheet being coated, the clutch 21 may be engaged to effect a direct driving connection between the shafts 26 and 28, the diameter of the rolls and the total ratio of the drive being such as to produce that result. This ratio, as well as the other ratios herein mentioned, will, of course, be preserved independently of the actual speed of operation of the entire machine, which may vary under different conditions.

The principal object of the invention, which is attained by driving the coating rolls at a peripheral speed greater than the lineal speed of the sheet being coated, is accomplished by manipulation of the clutches 35 and 35. When the clutch 35 is engaged, the driving connection to the rolls is completed through the sprocket wheels 38 and 4|, and, when the clutch 33 is engaged the driving connection is completed through the sprocket wheels 39 and 42. The former connection may suitably provide such a driving ratio as to operate the rolls at a peripheral speed equal to 150% of the lineal speed of the sheet, which I have found to produce particularly satisfactory results, and the latter connection may, for example, produce a peripheral roll speed equal to-% of the sheet speed. It will be understood, of course, that as many different speed ratios as desired may be provided and that peripheral roll speeds even greater than of the sheet speed may be utilized to advantage in some cases.

I have found that by increasing the peripheral speed of the rolls above the sheet speed an improved surface appearance is produced, even when the coating substance is particularly thick and heavy and even where the coating rolls are of relatively large diameter. The product has a fine, short grain of good appearance, which can be varied within desired limits by the use of the different excess speed ratios provided, the variations in effect being due to the different characteristics of adherence of the viscid coating substance to the rolls at the different speeds of the latter. As shown in Fig. 4, the web l2c, after application of the coating substance to both surfaces thereof, as indicated at 54, 54 passes through the nip of the rolls l1 and I8 where the applicationof the coating with the desired uniformity is completed. As the web I2d emerges from the rolls the coating substance adheres to the latter and strings out as indicated at 55, 55 by reason of its viscid nature.

Depending upon the ratio of the peripheral spasms speed of the rolls to the lineal speed of the sheet, these stringy particles of the coating substance will be drawn out to a greater or lesser extent before rupturing or pulling free of the rolls and will consequently produce different surface effects upon the coated sheet. The modulus of elasticity of the coating substance is such that it will stretch out to some extent-in any event, but the extent of stretching will decrease as the speed of the rolls is increased. In other words, when the strings of materials are drawn out relatively rapidly, they will rupture or separate from the rolls more rapidly than if they are pulled out relatively slowly, and it is by reason of this action that the variation in the speed of the rolls may be utilized to produce the desired-different surface effects on the coated material. The effect may also be enhanced or modified by the variations in centrifugal force due to the changes in roll speed. The term rupture" as used in the claims is intended to designate broadly either actual breaking of the strings of viscid coating material or the separation of the strings from the roll'surfaces.

The shorter the grain that is desired, the more the speed of the rolls is increased over the speed i of the sheet. For example, Fig. 5 of the drawings illustrates the line grain appearance of the product turned out when the rolls are operated at one speed ratio above the sheet speed, while Fig. 6 illustrates the coarser grained product made at a somewhat smaller increase of roll speed over the sheet speed. These products, if made with the coating rolls operating at a peripheral speed equivalent to or less than the lineal speed of the sheet, but otherwise under the same conditions,

would have an excessively coarse grain which,

would not be satisfactory.

For other types of products, however, it may be desirable to operate the machine with the coating rolls turning at a peripheral speed corresponding to or less than the lineal speed of the sheet, or to maintain the rolls stationary. The speed change mechanism herein disclosed, therefore, is adaptable to all of the conditions under which the machine may be operated, because it provides means for disconnecting the rolls from the driving means so that they can be maintained stationary and means for driving the rolls either ata very low rate of speed or at a speed corresponding to the sheet speed, as well as providing a selection of increased speeds which are desirable under certain conditions of operation.

The various speed changes are readily effected by simply engaging the required one of the clutches 21, 34, 35, or 36 (or by leaving them all disengaged) by means of the operating handles 50, 5|, 52, and 53. Much time is saved in changing the machine over from one type of operation to another, because it is unnecessary to provide a number of sets of rolls of different sizes to be interchanged for producing different results, and no other mechanical changes, except the selection of the desired roll speed by means of the change speed mechanism, are required.

The method of producing coated materials of the type herein referred to, by advancing the coated sheet in contact with roller surfaces mov-; ing in the same direction as the sheet but at a greater rate of speed, is of decided advantage in the production of desired surface effects, and the mode of accomplishing this operation, as well as accommodating changes in the ratio of roll speed to sheet speed by providing a change speed mechanism as herein disclosed, is also highly advantageous, and these features of the method are believed to be novel and are accordingly claimed herein, the apparatus being claimed in my above referred to prior application.

While only one specific embodiment of the invention has been shown and described herein, it will be readily understood by those skilled in the art that various changes and modifications in the details of design and arrangement of parts of the apparatus and in the mode of carrying out the process may be made without departing from the spirit and scope of the invention as set forth in the appended claims. For example, the sheet may be coated on either one or both surfaces, as desired, and any desired speed ratios other than those specifically mentioned herein may be provided for the operation of the coating rolls. It will also be understood that the rolls as well as other parts of the machine may be driven by any desired type of driving means or connections.

What is claimed as new and is desired to secure by Letters Patent, therefore, is:

1. The method of producing a coated sheet roofing material having a desired surface effect, which includes the steps of applying a viscid coating substanceto a sheet and advancing the sheet thus coated in contact with a surface to which said viscid coating tends to adhere while said surface is moving in the same direction as the sheet but at a higher rate of speed, the relative speed of said surface and the tendency of said viscid coating to adhere to said surface being such as to cause said viscid coating to string out and form a desired short grain discontinuous surface.

2. The method of producing a coated sheet roofing material having a desired surface effect. which includes the steps of applying a viscid coating substance to a sheet and advancing the sheet thus coated in contact with a surface to which said viscid coating tends to adhere while said surface is moving in the same direction as the sheet but at about one and one-half times the rate of speed thereof, the tendency of said viscid coating to adhere to said surface being such as to cause said viscid coating to string out roofing material having a desired surface effect,

which includes the steps of applying a viscid coating substance to both surfaces of a sheet and advancing the sheet thus coated between and in contact with surfaces to which said viscid coatings tend to adhere while said surfaces are moving in the same direction as the sheet but at a higher rate of speed, the tendency of said viscid coatings to adhere to saidsurfaces being such as to cause said coatings to string out and the speed of said surfaces being such as to cause the strings quickly to rupture and form short grain discontinuous surfaces.

4. The method of producing a coated sheet roofing material having a desired surface effect, which includes the steps of applying a viscid coating substance to both surfaces of' a sheet and advancing the sheet thus coated between and in contact with surfaces to which said viscid coatings tend to adhere while said surfaces are moving in the same direction as the sheet but at approximately one and one-half times the rate of speed, the tendency of said viscid coatings to adhere to said surfaces being such as to cause I 10 tends to adhere, and varying the rate of movement of the surface between different speeds in excess of the rate of advance of the sheet and in the same direction therewith to cause said coating substance to string out and rupture to obtain the particular surface. effect desired, the quickness of rupture of said strings depending upon the tendency of the viscid coating substance to adhere to said surface and the speed of said surface.

RALPH W. B. READE. 

